Cutting balloon catheter with flexible cutting blades

Abstract

A cutting balloon catheter including a balloon mounted on a distal portion of a catheter shaft. The balloon includes a cutting member mounted on an exterior surface of the balloon which includes one or more features for providing the cutting member with enhanced flexibility for navigating tortuous anatomy and more closely conforms to the expansion characteristics of the balloon to which the cutting member is mounted.

What is claimed is: 
     
       1. A medical balloon catheter comprising:
 a catheter shaft; 
 an inflatable balloon secured to a distal portion of the catheter shaft; 
 a cutting member extending from a first end to a second end and having a first portion and a second portion, each portion including a cutting edge and a base portion; 
 a mounting pad for securing the base portion to the inflatable balloon; 
 wherein the first portion and the second portion of the cutting member are connected by at least one region of enhanced flexibility between the first end and the second end of the cutting member; 
 wherein each region of enhanced flexibility includes at least one vertical slot extending from the cutting edge; 
 wherein each one of the at least one vertical slot includes a first open end proximate the cutting edge and a second closed end proximate the base portion; 
 wherein the second closed end includes an enlarged region having a width larger than a width of a remainder of the at least one vertical slot; and 
 wherein the region of enhanced flexibility is configured to allow the first portion to flex relative to the second portion without fracturing the first portion from the second portion. 
 
     
     
       2. The medical balloon catheter of  claim 1 , wherein the at least one vertical slot extends toward the base portion. 
     
     
       3. The medical balloon catheter of  claim 1 , wherein the cutting edge of the first portion is discontinuous from the cutting edge of the second portion. 
     
     
       4. The medical balloon catheter of  claim 3 , wherein the base portion of the first portion is discontinuous from the base portion of the second portion. 
     
     
       5. The medical balloon catheter of  claim 1 , wherein the base portions of the first portion and the second portion include a plurality of slots formed along a length of the base portions. 
     
     
       6. The medical balloon catheter of  claim 5 , wherein each of the plurality of slots has a T-shape with a horizontal segment having a first end and a second end and a vertical segment intersecting the horizontal segment intermediate the first end and the second end, the vertical segment opening to a lower surface of the cutting member. 
     
     
       7. A medical balloon catheter comprising:
 a catheter shaft; 
 an inflatable balloon secured to a distal portion of the catheter shaft; and 
 a cutting member mounted on the balloon, the cutting member including:
 a first portion having a first cutting edge and a first base portion; 
 a second portion having a second cutting edge and a second base portion; and 
 at least one region of enhanced flexibility connecting the first portion and the second portion and configured to allow the first portion to flex relative to the second portion without fracturing the first portion from the second portion, wherein each region of enhanced flexibility includes a vertical slot extending radially from the cutting edges towards the base portions; 
 wherein the vertical slot includes a first open end between the first and second cutting edges and a second closed end proximate the first and second base portions; 
 wherein the second closed end includes an enlarged region having a width larger than a width of a remainder of the vertical slot. 
 
 
     
     
       8. The medical balloon catheter of  claim 7 , wherein the first and second base portions of the first and the second portions include a plurality of slots formed along a length of the first and second base portions. 
     
     
       9. A medical balloon catheter comprising:
 a catheter shaft; 
 an inflatable balloon secured to a distal portion of the catheter shaft; and 
 a cutting member secured to the balloon, the cutting member having a first end and a second end and including:
 a first portion that includes the first end, a first cutting edge, and a first base portion; 
 a second portion that includes the second end, a second cutting edge, and a second base portion; and 
 a region of enhanced flexibility connecting the first portion and the second portion and configured to allow the first portion to flex relative to the second portion without fracturing the first portion from the second portion, wherein the region of enhanced flexibility includes a vertical slot extending from the cutting edges towards the base portions; 
 wherein the vertical slot includes a first open end between the first and second cutting edges and a second closed end proximate the first and second base portions wherein the second closed end includes an enlarged region having a width larger than a width of a remainder of the vertical slot.